The leaders of the Sept. 11 commission (search) implored Congress to move quickly to reform the nation's intelligence structure, warning Friday that failure to act would leave America vulnerable to another devastating terrorist attack.

A working group appointed by President Bush (search) also continued its meetings Friday, and a senior White House official, who spoke only on the condition of anonymity, said it was close to presenting a package of reforms to Bush.

Among the ideas prompting discussion is the establishment of a new national intelligence director, one of the key proposals from the 9/11 commission. The official said the administration's internal debate has centered on the scope of that person's authority and how the individual would work with the CIA (search).

In an unusual Senate hearing during summer recess on Capitol Hill, the 9/11 commission's chairman, Thomas Kean, and vice chairman Lee Hamilton acknowledged institutional resistance to change will make reforms difficult, but said the status quo is not an option.

Key senators on the Senate Governmental Affairs Committee (search) pledged to swiftly but thoughtfully consider the commission's proposals.

The panel has recommended some 40 changes, but Friday's hearing focused mostly on two: creation of a new national counterterrorism center and a new national intelligence director to oversee the 15-agency intelligence community.

"We have concluded the intelligence community is not going to get its job done unless somebody really is in charge," Hamilton, a former Democratic congressman from Indiana, told the Senate committee. "That is just not the case now, and we have paid the price."

Intelligence reform has become a key issue in the fall election, with Kean, Hamilton and other commissioners vowing to keep the pressure on Congress and the Bush administration to make changes.

Democratic presidential candidate John Kerry has endorsed the commission findings. Bush has created a working group to study the recommendations and draft executive orders that could immediately implement some of the proposals.

The senior White House official, speaking anonymously because policy proposals remain under discussion, laid out three principles to guide the group's debate: increase human intelligence capabilities, maintain the country's technical collection advantage over the enemy, and improve coordination among agencies in the intelligence community.

Without providing specifics, the official said the working group is looking at options that could go beyond what the commission recommended, but indicated that one focus might be in the area of protecting privacy rights and civil liberties.

"Reform is not easy," Bush said at a campaign stop in Springfield, Mo. "Achieving reform requires taking on the special interests, requires challenging the status quo."

The commission's widely acclaimed report recounted numerous intelligence missteps in the months preceding the 2001 terror attacks against New York and Washington that killed nearly 3,000 people.

The 10 commissioners, traveling in pairs, are embarking on a nationwide tour next week to share their report with the public and to draw attention to the need for intelligence reforms. Kean said the commission is seeking private donations to continue the panel's work past Aug. 26, when it is scheduled to dissolve.

Kean attributed pre-9/11 intelligence failures to a profound lack of coordination across intelligence agencies.

"No one was the quarterback, no one was calling the plays," Kean said. In the proposed reorganization, he said, "each agency needs to give up some of their existing turf and some of their authority."

During the hearing, Kean called it "unacceptable" that the recently departed CIA Director George Tenet asserted that the country is five years from an adequate clandestine service.

However, Kean and Hamilton praised reforms already undertaken by FBI Director Robert Mueller, who has sought to transform the bureau's priority from criminal investigations to counterterrorism.

Committee Chairwoman Susan Collins, R-Maine, urged fellow lawmakers to "be bold but not reckless" in considering changes that will lead to what she described as a "fundamental overhaul of our intelligence structure and a sea change in our thinking."

The committee's ranking Democrat, Joseph Lieberman of Connecticut, promised that, "We're going to get this job done and get it done with unprecedented thoughtfulness and speed."

Collins and Lieberman support the proposed national intelligence director and national counterterrorism center. But both are still looking for more details on how it would work.

For instance, Collins questioned whether the national intelligence director should be part of the Cabinet, which the commission did not recommend because Kean said the job would be an operational — and not policy — position.

Congressional critics are surfacing as well. Sen. Carl Levin, D-Mich., questioned whether the new national intelligence director would be too close to the White House to provide much-needed independent analysis. And he said he has reservations about what the counterterrorism center will mean for the command structure at the Defense Department.

Homeland Security Secretary Tom Ridge said during a trip to Miami that the administration was open to additional changes.

"I think right now, for our purposes, everything is out on the table," Ridge said. "If there's still gaps there, if we need to do it, then we need to work with Congress and we use the recommendations as a starting point for that conversation."

The hearing was the first of at least 15 that will be held in the coming weeks by more than a half-dozen House and Senate committees.